Figure 1

Simplified conceptual UML object model used in VarioML. The VarioML object model is derived from Observ-OM (http://www.observ-om.org/wiki/ObservStart), with some modifications to simplify implementation. E.g., Observable Feature (such as phenotype or mutation name) and Observed Value (existence of phenotype or variation) are denormalized into a single XML element. This avoids unnecessary nesting of observation elements which do often have one-to-one relationship, in the XML implementation. Entities are composed into Observations, having properties such as evidence codes, observation protocols and observation time. Associations between elements are described as single lines, where an asterisk means a 0-to-many multiplicity relationship; i.e. Observation can have one or many evidence codes. All entities also inherit from Annotatable properties which are needed for database cross references and comments. In this case, the open arrow symbol means inheritance or an is-a relationship.